Brake Cooling

[johnthomas]

Has anyone with a 996TT installed the GT3 brake ducts? If so, please advise on benefits and disadvantages as well as installation issues.

[JimB]

In your title you referred to GT3 Cup Car ducts so I'm assuming that is what you are asking about rather than the GT3 street car. I use the cup car cooling ducts on my 996 track car. My front end should be pretty much the same as your TT.

They are made up of two pieces per side. One piece captures air that passes through the radiator and directs it towards the rotors. This part snaps easily into place and should work on your car. You might want to increase the size of the slots in your wheel well liner to improve it's effectiveness.

The other snaps on a lower control arm and directs air from under the car towards the rotors. It is actually just a larger version of the stock ones. This one will be a real problem on the street. It hangs down very low. I doubt it will last very long.

Hope this helps.

Jim

[03-turbo911]

I have that exact same set-up on my tt plus GT2 rear ducts. I have yet to test it's effectiveness in track conditions, but I have no clarence problems with it.

[Alex4747]

I have that exact same set-up on my tt plus GT2 rear ducts. I have yet to test it's effectiveness in track conditions, but I have no clarence problems with it.

There is a TSB that states that the ducts are not to be used in the TT with ceramic brakes. Check the TSB about the ducts.

[03-turbo911]

Thanx Alex for the TSB info, but I don't have ceramics. :)

[jasonc]

I have that exact same set-up on my tt plus GT2 rear ducts. I have yet to test it's effectiveness in track conditions, but I have no clarence problems with it.

There is a TSB that states that the ducts are not to be used in the TT with ceramic brakes. Check the TSB about the ducts.

Is that just a non-approval, or does the TSB mean there is a potential problem with using them? I read one of the TSB's which seemed a bit vague. Maybe I was looking at teh wrong one. Do you have a TSB number?

[03-turbo911]

I just came from a wonderful day at the track. Me and a few friends rented it out for the afternoon and among the cars present, was one RUF RGT2 (550BHP), two 996 turbos, one of which is mine, one GT3, one BMW M3 CSL, and two Mitsubishi Evos.

I was interested in seeing how the mods I have installed will do in a track setting. I have the Cup car brake cooling ducts in the front. GT2 ducts in the back, hardened engine mounts, and GT3 rear sway bar on my ROW suspension.

Last time I had run on the track, my car was ROW stock, and by the third lap, my brakes were fading fast so my attempt at installing the brake ducts was a "cheap" way of trying to delay the enevitable brake fade. I am happy to say that after three laps my brakes were much better in that respect. Although I did feel a degradation of there effectiveness in comparision with my first lap, the braking performance was not that affected as with the stock ducts. The hardened engine mounts made the car a bit stiffer in the back and, curiously, the exhaust note was more pronounced. The GT3 bar was, in my opinion, the best mod I did after the ducts. The car felt more balanced and I could feel the car being more neutral and not apt to understeering at the slightest opportunity.

The lesson that I learned was that I do need to go to a different brake compound from the stock pads. The best option is to upgrade the brakes with something more effective. The tires were the stock Pirellis which are fine for the street, but for the track, I need a stickier tire. The suspension needs more work. I will try to adjust camber from the stock setting, to around 1.5 degrees negative. Coilovers and a front GT3 sway bar is on my wish list as well.

If you want to stay satisfied with your 996tt, then please don't take it out on a track. You will, easily, drain your bank account trying to make your 996tt into a cup car, a role it was not designed to do. My advice is to avoid tracking like the plague. It is so infectious. :P